As \(\hat{\gamma }\)  we recommend using the [1]} estimator given by
\(\hat{\gamma }_P = \dfrac{1}{\ln 2} \ln \dfrac{\vartheta _{N-k, N}- \vartheta _{N-2k, N} }{\vartheta _{N-2k, N} - \vartheta _{N-4k, N}},\) 
